package day;

import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

public class Hannuo {

    /**
     * 将 n借助a移动到b
     *
     * @param n
     * @param a
     * @param b
     */
    public void hannuo(int n, char a, char b, char c) {
        if (n == 1) {
            System.out.println(n + "\t" + a + " -> " + c);
            return;
        }
        hannuo(n - 1, a, c, b);
        System.out.println(n + "\t" + a + " -> " + c);
        hannuo(n - 1, b, a, c);
    }

    public static void main(String[] args) {
        //new Hannuo().hannuo(3, 'a', 'b', 'c');
        Map<String,String> map=new ConcurrentHashMap<>();
        map.put(null, null);
        System.out.println(map.get(null));
    }

}
